Research Journal of Applied Sciences, Engineering and Technology 6(24): 4569-4574, 2013
ISSN: 2040-7459; e-ISSN: 2040-7467
© Maxwell Scientific Organization, 2013
Submitted: December 31, 2012
Accepted: January 23, 2013
Published: December 25, 2013
Analysis for Suspension Hardpoint of Formula SAE Car Based on Correlation Theory
Xintian Liu, Jiao Luo, Yansong Wang, Hui Guo and Xinyu Wang
College of Automotive Engineering, Shanghai University of Engineering Science at Shanghai, Shanghai
201620, China
Abstract: According to the correlation of the hardpoints, double wishbone suspension of Formula SAE Car can be
improved and optimized. For Formula SAE car, performance and kinetic characteristic of the suspension follow very
closely to handling stability, comfort ability, handling of steering and service life of tire, etc. Double wishbone
suspension is chosen as front suspension of Formula SAE car in the paper. Based on the multi-body dynamics and
suspension kinematics theory, simulation model of front suspension is built and analyzed. With correlation theory,
the correlation for the hardpoints of the suspension is studied and discussed. Through all the testing, not only a lot of
four wheel alignment parameter variations can be obtained, but also the rational designing for hardpoints which can
provide an useful reference for vehicle designing.
Keywords: Correlation theory, double wishbone suspension, formula SAE car, simulation model
INTRODUCTION
The suspension system plays an important role
with regard to the performance of a vehicle in terms of
its handling ability, stability, and ride comfort. Double
wishbone independent suspension is widely used on
automobile now. Two wishbones have equal length or
not. Equal length of double wishbone independent
suspension is not usually used now. Unequal length of
double wishbone independent suspension can keep
good road ability and reduce the interference between
suspension and steer bar, with reasonable structural
parameters and proper arrangements to make the
parameter of wheel spin and wheel location floating in
permissible range. Stabilization of Formula SAE Car
with high speed is more important than ride comfort
(William and Douglas, 1995). Considering space and
placement of Formula SAE Cars, double wishbone
suspension is chosen in the countries all over the world.
Unequal length of double wishbone suspension can
keep good stabilization and have suitable roll center and
longitudinal tipping Center with the right hardpoints
and the length of control arm (Shun-Kai et al., 2006).
Modeling and simulation of suspension systems
exist in a significant number of publications, for
example, M´antaras et al. (2004) and Cronin (1981).
Similarly, the double wishbone suspension is modeled
and simulated dynamically (Attia, 2001; Liu et al.,
2010). There are very few papers to analyze and discuss
the design and optimization of the suspension system.
The existing suspension systems redesigned or
optimized by eliminating or reducing a certain defect or
fault inherent during the suspension design (Bian et al.,
2004; Habibi et al., 2007). A better suspension system
can be obtained by improving or optimizing the existing
and working suspension. The effect of the suspension
kinematics on the vehicle handling characteristics and
perform vehicle handling simulations is studied (Lee
et al., 2001; Makita, 1999). The kinematic model of the
suspension is actively applied to obtain optimum ride
and handling characteristics. Apparently, there have not
been focused efforts on methods to design and optimize
suspension for quantitative ride characteristics. The
conclusion is some hardpoints will have heavy effect on
suspension characteristic and performance by the
hardpoint correlation. The hardpoint correlation can
provide a reference for improvement or optimization of
the suspension.
Front double wishbone independent suspension is
regard as research object (Li et al., 2003; Liu et al.,
2011), using multi-body dynamics and suspension
kinematics theory to analyze and discuss the correlation
for the hardpoints of the suspension. With the
correlation of the hardpoints, the performance of front
suspension can be improved and optimized.
DOUBLE WISHBONE FRONT
SUSPENSION MODEL
There are 12 Hardpoints in the double wishbone
front suspension of Formula SAE (Badih and Brian,
2002). One-half front suspension has 6 Hardpoints as
follows in Fig. 1. Connection points between upper
control arm and the frame are hardpoint 1 and 2.
Corresponding Author: Xintian Liu, College of Automotive Engineering, Shanghai University of Engineering Science at
Shanghai, Shanghai 201620, China
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Res. J. Appl. Sci. Eng. Technol., 6(24): 4569-4574, 2013
Fig. 1: One-half front suspension
Fig. 2: Parameters of unequal length front suspension
wheel travel, which can reduce the wear of the tire and
extend its serviceable life. So that length ratio between
upper control arm and lower control arm is about 0.6.
To keep good stabilization, racing wheel alignment
parameters should have small change. At this moment
length ratio between upper control arm and lower
control arm is about 1.0. To sum up the above
arguments, the range of length ratio is 0.6 to 1.0.
Front suspension model of Formula SAE Car is
built based on multi-body dynamics and Suspension
Kinematics theory in Fig. 2. The hardpoints of front
suspension is as follows in Table 1.
Front suspension simulation model are built and
showed as in the Fig. 3. Changes of wheel alignment
parameters are directly affected by design rationality of
guiding mechanism in an independent suspension with
double wishbone. To meet racing car’s performance
need, Changes of wheel alignment parameters should
be kept within reasonable bounds. Wheel alignment
parameters are analyzed and discussed in this paper, for
example, camber angle, caster angle, kingpin angle and
toe angle.
HARDPOINTS CHANGE ANALYSIS OF
FRONT SUSPENSION
Hardpoints change related to X axis: The value of
hardpoint 1 is changed at X-axis incrementally by δx
2mm, while keeping the other hardpoints unchanged.
During the move of hardpoint 1, the change of
hardpoint 1 maybe interferes with shock absorber and
the rocker. The camber changes about 0.01°, caster with
0.006°, kingpin 0.01° and toe-in 0.04°. In a word, the
move of hardpoint 1 has slight effect on wheel
alignment parameters.
The value of hardpoint 2 is changed at X-axis
incrementally
by δx 20 mm, while keeping the other
Fig. 3: Front suspension simulation model
hardpoints unchanged. The change of hardpoint 2 has a
wide range at X-axis. During the move of hardpoint 2,
Table 1: The hardpoints of front suspension
the camber changes about 0.02°, caster with 0.015°,
The hardpoint
X (mm)
Y (mm)
Z (mm)
kingpin 0.01° and toe-in 0.004°. where x=728.389,
Hardpoint 1
440.988
-288.526
205.629
Hardpoint 2
828.389
-288.526
201.415
there are abnormal value of caster 0.1888, but all other
Hardpoint 3
521.200
-581.044
232.087
parameters have slight change. So that x = 728.389 is
Hardpoint 4
303.347
-171.947
18.200
not normally present in the hardpoint design. In a word,
Hardpoint 5
701.268
-171.947
18.200
the move of hardpoint 2 has slight effect on wheel
Hardpoint 6
506.500
-581.044
22.010
alignment parameters.
The value of hardpoint 4 is changed at X-axis
Connection points between lower control arm and the
incrementally
by δx 2 mm, while keeping the other
frame are hardpoint 4 and 5. Connection point between
hardpoints unchanged. During the move of hardpoint 4,
upper control arm and the column is hardpoint 3.
the change of hardpoint 4 maybe interferes with shock
Connection point between lower control arm and the
absorber and the rocker. During the move of hardpoint
column is hardpoint 6. Hardpoint 3 and 6 are obtained
4, the camber changes about 0.001°, caster with 0.002°,
with the length of kingpin and wheel alignment
kingpin 0.01° and toe-in 0.001°. In a word, the move of
parameters. All other hardpoints can be used to decide
hardpoint 4 has slight effect on wheel alignment
the parameters of double wishbone suspension and its
parameters.
performance. The placement of six hardpoints affects
The value of hardpoint 5 is changed at X-axis
suspension performance and stabilization.
incrementally by δx 2 mm, while keeping the other
The length of upper control arm or lower control
hardpoints unchanged. During the move of hardpoint 5,
arm has a great effect on wheel alignment parameters.
the change of hardpoint 5 maybe interferes with shock
Racing wheel tread should have small change when
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absorber and the rocker. During the move of hardpoint
5, the camber changes about 0.001°, caster with 0.001°,
kingpin 0.001° and toe-in 0.002°. In a word, the move
of hardpoint 5 has slight effect on wheel alignment
parameters.
As stated above, four hardpoints are changed at Xaxis. And the move of the hardpoints has slight effect
on wheel alignment parameters. Then suspension
hardpoints can be changed according to hardpoint
layout because of slight performance change for wheel
alignment parameters.
with △max = 0.006. Thus, the Y value for hard point 4
should fall into set [141.947, 201.947] considering of
the comparatively reasonable solution for caster design
and changing four-wheel alignments.
The value of hardpoint 5 is changed at Y-axis
incrementally by δy 3 mm, while keeping the other
hardpoints unchanged. Since the Y-value would have
impact on the length of rocker arm, while the length
ratio of the two arms should be set between 0.6 -0.8, the
allowance for changes should be controlled between
±30mm. When the y-value increase, the length of rear
lower wishbone would increase and camber decrease
with △max equals to 0.0013. However, the caster
would incline to increase with the maximum △value of
0.0514, so does the kingpin with △max = 0.0061. In the
meanwhile, the toe-in would increase instead with
△max = 0.057. Thus, the Y value for hard point 5
should fall into set [141.947, 201.947] considering of
the comparatively reasonable solution for caster design
and changing four-wheel alignments.
As stated above, four hardpoints are changed at Xaxis. Hard piont 1 has heavy effect on wheel alignment
parameters. But the move of all other hardpoints has
slight effect on wheel alignment parameters.
Hardpoints change related to Y axis: The value of
hardpoint 1 is changed at Y-axis incrementally by δY
3mm, while keeping the other hardpoints unchanged.
Since the Y-value would have impact on the length of
rocker arm, while the length ratio of the two arms
should be set between 0.6-0.8, the allowance for
changes should be controlled between ±30mm. When
the y-value increase, the length of front upper wishbone
would increase and camber decrease with △max equals
to 0.2253. In the meanwhile, the caster would incline to
decrease with the maximum △value of 0.015, so does
the kingpin with △max = 0.2075. However, the toe-in
would increase instead with △max = 0.2376. Thus, the
Y value for hard point 1 should fall into set [258.526,
Hardpoints change related to Z axis: The value of
288.526] considering of the comparatively reasonable
hardpoint 1 is changed at Z-axis incrementally by δz
solution for caster design and changing four-wheel
3mm,
while keeping the other hardpoints unchanged.
alignments.
As the allowance for changing of Z value is larger than
The value of hardpoint 2 is changed at Y-axis
on other directions, the allowance can be set between
incrementally by δy 3 mm, while keeping the other
±30 mm. With the Z value increases, the front upper
hardpoints unchanged. Since the Y-value would have
wishbone would slant and the camber would decline
impact on the length of rocker arm, while the length
with the maximum change at 2.0067, caster increase
ratio of the two arms should be set between 0.6-0.8, the
with △max = 0.1995, the kingpin decrease with △max
allowance for changes should be controlled between
= 2.1127, and toe-in increase by maximum 1.9495.
±30mm. When the y-value increase, the length of rear
When hardpoint 1 moves between [175.629，205.629]
upper wishbone would increase and camber decrease
at Z-direction, the camber would not change in
with △max equals to 0.0514. In the meanwhile, the
according with the compression and explanation of
caster would incline to decrease with the maximum
springs. In this circumstance, danger of unnecessary
△value of 0.0069, so does the kingpin with △ max =
damage of kingpin would occur during driving of the
0.0479. However, the toe-in would increase instead
vehicle if this design would be utilized. Thus, the most
with △max = 0.0645. Thus, the Y value for hard point 2
suitable interval for Z-value should be set between
should fall into set [258.526, 300.526] considering of
[205.629, 220.629] for hardpoint 1.
the comparatively reasonable solution for caster design
The value of hardpoint 2 is changed at Z-axis
and changing four-wheel alignments.
incrementally by δz 3mm, while keeping the other
The value of hardpoint 4 is changed at Y-axis
hardpoints unchanged. As the allowance for changing
incrementally by δy 3mm, while keeping the other
of Z value is larger than on other directions, the
hardpoints unchanged. Since the Y-value would have
allowance can be set between ±30 mm. With the Z
impact on the length of rocker arm, while the length
value increases, the rear upper wishbone would slant
ratio of the two arms should be set between 0.6 -0.8, the
and the camber would decline with the maximum
allowance for changes should be controlled between
change at 0.6116, caster increase and then decrease, the
±30mm. When the y-value increase, the length of front
kingpin decrease with △max = 0.5431, and toe-in
lower wishbone would increase and camber increase
increase by maximum 1.002. When hardpoint 2 moves
with △max equals to 0.0118. In the meanwhile, the
between [201.415，231.415] at Z-direction, the camber
caster would incline to decrease with the maximum
would not change in according with the compression
and explanation of springs. In this circumstance, danger
△value of 0.0479, so does the kingpin with △max =
of unnecessary damage of kingpin would occur during
0.0116. However, the toe-in would increase instead
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driving of the vehicle if this design would be utilized.
Thus, the most suitable interval for Z-value should be
set between [180.415, 201.415] for hardpoint 2.
The value of hardpoint 4 is changed at Z-axis
incrementally by δz 3mm, while keeping the other
hardpoints unchanged. As the allowance for changing
of Z value is larger than on other directions, the
allowance can be set between ±30 mm. With the Z
value increases, the front lower wishbone would slant
and the camber would increase with the maximum
change at 0.9992, caster increase and then decrease, the
kingpin decrease with △max = 1.3379, and toe-in
decrease and then increase. When hardpoint 4 moves
between [18.2, 48.2] at Z-direction, the camber would
not change in according with the compression and
explanation of springs. In this circumstance, danger of
unnecessary damage of kingpin would occur during
driving of the vehicle if this design would be utilized.
Thus, the most suitable interval for Z-value should be
set between [0.2, 18.2] for hardpoint 4.
The value of hardpoint 5 is changed at Z-axis
incrementally by δz 3mm, while keeping the other
hardpoints unchanged. As the allowance for changing
of Z value is larger than on other directions, the
allowance can be set between ±30mm. With the Z value
increases, the rear lower wishbone would slant and the
camber would increase with the maximum change at
0.4852, caster increase and then decrease, the kingpin
increase with △max = 0.7498, and toe-in decrease and
then increase. When hardpoint 5 moves between [-12.2,
18.2] at Z-direction, the camber would not change in
according with the compression and explanation of
springs. In this circumstance, danger of unnecessary
damage of kingpin would occur during driving of the
vehicle if this design would be utilized. Thus, the most
suitable interval for Z-value should be set between
[18.2, 24.2] for hardpoint 5.
Stated thus, 4 hardpoints are changed at X-axis. All
the hardpoints has heavy effect on wheel alignment
parameters.
1-2 and 4-5 change related to Z axis: Change the
value of hardpoint 1 and hardpoint 2 at Z direction with
a 3 mm margin every time with other points unchanged,
the slant of upper cross arm would affect four-wheel
alignment positioning performance. However, when a
small caster change occurs, the proper position can be
detected when the Z value of the front and rear point is
close enough based on the previous test.
Change the value of hardpoint 4 and hardpoint 5 at
Z direction with a 3mm margin every time with other
points unchanged. According to the analyses, the
conclusion is consistent with the change of hardpoint 1
and hardpoint 2 at Z direction.
The change for hardpoint 3 and 6: Hard point 3 and 6
have heavy effect on the column location and wheel
tread. Because hardpoint 3 and 6 have heavy effect on
the layout of racing car at X-axis and Z-axis, hardpoint 3
and 6 are not analyzed and discussed. Change the value
of hardpoint 3 and hardpoint 6 at X direction with a
2mm margin every time with other points unchanged.
When wheel tread is increased, camber has small
change. However caster has a slight change, kingpin
decrease, and toe increase. In a word, considering
suspension performance and racing trafficability,
unchanged front tread can be suitable.
THE ANALYSIS AND DISCUSSION OF THE
HARDPOINTS CORRELATION
As stated above, with correlation theory, the
correlation for the hardpoints of the suspension is
studied and discussed. The result for the correlation of
the hardpoints is shown as in the Table 2.
According to Table 2, the correlations between the
changes of hardpoint 1, 2 are high for steering axis
inclination, camber and toe-in at Y direction, which
means that no matter how the hardpoints change would
not affect the four-wheel alignment parameters. Since
the change of caster would affect the four-wheel
1-2 and 4-5 change related to Y axis: Change the Yalignment parameters, the change of caster would be
value of hardpoint 1 and hardpoint 2 incrementally by
minimized when the Y value of hardpoint 1 and 2 are
△x = 3 mm every time with other points unchanged, the
close enough to get the proper caster.
equalized amount of change implies that the length of
For hardpoint 4 and 5, the changes of value at Ythe upper control arm would change accordingly, which
axis would have a bigger impact on the four-wheel
would have a bigger impact on the four-wheel
alignment parameters based on the correlation
alignment parameters. Therefore，a validation test of
perspective. However, the absolute amount of the
comparison between the upper and lower control arms
parameters does not change a lot besides the camber,
should be conducted to obtain the rational parameters
which shows a better results when the Y-value of
for the upper control arm.
hardpoint 5 is less than that of hardpoint 5.
Change the Y-value of hardpoint 4 and hardpoint 5
When moves the upper cross arm (hardpoint 1-2)
incrementally by △x = 3 mm every time with other
and lower cross arm (hardpoint 4-5), it is shown similar
points unchanged, the equalized amount of change
results that the co-efficiencies are high enough to prove
implies that the length of the lower control arm would
the significances except the caster. Since the changes for
change accordingly, which would have a bigger impact
Y-values of the upper and lower cross arms would be
on the four-wheel alignment parameters. Therefore，a
equal to the changing of upper and lower cross arms
validation test of comparison between the upper and
ratio, it should be suitable to fit into the interval of 0.6lower control arms should be conducted to obtain the
rational parameters for the lower control arm.
0.8.
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Table 2: The correlation of the hardpoints
Hardpoint 1and 2 at Y-axis
Hardpoint 1 and 1-2 at Y-axis
Hardpoint 2 and 1-2 at Y-axis
Hardpoint 4 and 5 at Y-axis
Hardpoint 4 and 4-5 at Y-axis
Hardpoint 5 and 4-5 at Y-axis
Hardpoint 1-2 and 4-5 at Y-axis
Hardpoint 1 and 2 at Z-axis
Hardpoint 1 and 1-2 at Z-axis
Hardpoint 2 and 1-2 at Z-axis
Hardpoint 4 and 5 at Z-axis
Hardpoint 4 and 4-5 at Z-axis
Hardpoint 5 and 4-5 at Z-axis
Hardpoint 4 and 4-5 at Z-axis
Camber
0.995434
0.99743
0.991326
0.916882
0.986685
0.867965
-0.99541
0.988715
0.992243
0.990393
0.99997
0.999843
0.999856
-0.99697
Caster
0.692997
0.002895
-0.13107
-0.99987
-0.99597
-0.99606
0.049924
0.850493
0.429646
-0.0439
0.894976
-0.36577
0.036961
0.939289
When referring to the movements on Z-axis for
hardpoint 1 and 2, the changes are significant enough
except the caster, which is similar with other results.
Based on the data listed at the Table 2, when the Z-value
decreases at hardpoint 1, a better performance is shown
which would coincide with the theories for hardpoints
arrangements. Meanwhile, based on the correlations of
these parameters, it is much more stable for caster when
decreases the Z-values of the two points in the same
time.
The findings also show the same results when
changing the values of hardpoint 4 and 5 at Z-direction.
When reached out the maximum for distance changes,
some of the four-wheel alignment parameters would
change 2° at most. Based on data shown at Table 2, it
would show a better result when decreasing the Z-value
of hardpoint 4. Like hardpoint 1 and 2, decreasing the
values of point 4 and 5 simultaneously would generate a
more satisfied result.
Based on Table 2, it is showed that the parameters
displayed when the hardpoint 1-2 moves up and point 45 down at Z-axis would fit the requirements for
designing a Formula SAE Car. At this circumstance, the
upper and lower cross arms are almost parallel with each
other which means that when the 3 hardpoints of the
upper arm and 3 points at the lower cross arm can exert
a flat surface or parallel each other would produce the
beast performance for suspension system of the vehicle.
CONCLUSION
It is addressed that how a Formula SAE car front
suspension is designed based on calculations of
hardpoints of the suspension based on kinematic
simulation. The data generated by the software would
provide evidences and directions for the production
process.
Firstly, a double wishbone independent suspension
as the front suspension system chosen based on the
requirements and characteristics of Formula SAE cars.
Secondly, optimization of front suspension hard points
arrangements: the virtual simulation model for the front
suspension system of Formula SAE is built. Then, the
hardpoints arrangements are changed each time and the
data of parameter variations is obtained at different
conditions with kinematics simulation analysis. Finally,
Kingpin
0.995665
0.999696
0.99308
0.996255
0.987886
0.972537
-0.997800
0.999991
0.999869
0.999883
0.999972
0.999989
0.999983
-0.99974
Toe
0.996698
0.999804
0.994909
0.885703
0.832776
0.994346
0.999909
0.998651
0.96355
0.952362
0.98591
0.822081
0.897772
0.817461
the optimal arrangements for virtual can be obtained
according to the correlation test of each hardpoint.
According to the hardpoint correlation, the
parameters displayed when the hardpoint 1-2 moves up
and point 4-5 down at Z-axis would fit the requirements
for designing a Formula SAE Car. So the performance
of the suspension can be improved and optimized by
adjust the hardpiont 1, 2, 4 and 5 at Z-axis. A reference
can be provided for improvement or optimization of the
suspension with the hardpoint correlation. And the
scheme of the suspension can be made based on the
correlation and virtual experiment.
Through all the testing, not only a lot of four wheel
alignment parameter variations can be obtained, but also
the rational designing for hardpoints which can provide
an useful reference for vehicle designing. For future
events like SAE, players can continue to test virtual data
by simulation model or conduct analysis both on virtual
model and real car which can compare the tests to
improve the designing process and validity.
ACKNOWLEDGMENT
This study was supported by the National Natural
Science Foundation of China (Grant No. 51175320 &
51105241), Innovation Program of Shanghai Municipal
Education Commission (13YZ110), the Shanghai
Young University Teachers Training Aid program by
Shanghai Municipal Education Commission (No
shgcjs011), and the Shanghai University of Engineering
Science for Development of Science and Technology
(Grant No. 2011xy28).
REFERENCES
Attia, H.A., 2001. Dynamic modelling of the double
wishbone motor-vehicle suspension system. Europ.
J. Mech., 21(1): 167-174.
Badih, A.J. and D.P. Brian, 2002. Design of formula
SAE suspension components. Proceeding of the
SAE Motorsports Engineering Conference and
Exhibition, pp: 382.
Bian, X.L., B.A. Song and W. Becker, 2004. The
optimisation design of the McPherson strut and
steering mechanism for automobiles. Forschungim
Ingenieurwesen, 68(1): 60-65.
4573
Res. J. Appl. Sci. Eng. Technol., 6(24): 4569-4574, 2013
Cronin, D.L., 1981. MacPherson strut kinematics. Mech.
Mach. Theory, 16(6): 631-644.
Habibi, H., K.H. Shirazi and M. Shishesaz, 2007. Roll
steer minimization of McPherson-strut suspension
system using genetic algorithm method. Mech.
Mach. Theory, 43(1): 57-67.
Lee, S.H., U.K. Lee and C.S. Han, 2001. Enhancement
of vehicle handling characteristics by suspension
kinematic control. Proc. Inst. Mech. Eng., 215:
197-216.
Li, X., Y. Zhang, L. Zhou and M. Peng, 2003.
Characteristic analysis and calculation of wishbone
independent suspension with torsion bar. Automot.
Eng., 25(1): 15-19.
Liu, X., H. Huang, L. Zhao, W. Jichang, G. Hui, et al.,
2010. Influence of front double wishbone
independent suspension performance on rubber
bushing stiffness of the wishbone. Mach. Design
Manuf., 9: 116-117.
Liu, X., L. Zhao, H. Huang, Y. Wang and H. Chen,
2011. Influence of outer rubber bushing stiffness of
the under control arm on multi-link independent
suspension performance. Adv. Mech. Eng., 52-54:
578-582.
M´antaras, D.A., P. Luque and C. Vera, 2004.
Development and validation of a three-dimensional
kinematic model for the McPherson steering and
suspension mechanisms. Mech. Mach. Theory,
39(6): 603-619.
Makita, M., 1999. An application of suspension
kinematics for intermediate level vehicle handling
simulation. Soc. Autom. Eng. Japan, 20(4): 471477.
Shun-Kai, Y., S. Chuan-Xue, W. Shi-Ze and P. Ji, 2006.
Analysis of kinematics and elastokinematics
characteristics between multi-link and double
wishbone suspension. Automobile Technol., 12: 58.
William F.M. and L.M. Douglas, 1995. Race Car
Vehicle Dynamics. Society of Automotive
Engineers, Warrendale, Pa, pp: 890, ISBN:
1560915269.
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